Integrated Switch(PT6910)

The PT6910 is a continuous mode inductive step-down converter, designed for driving single or multiple series white LEDs efficiently from a voltage source higher than the output LED voltage. The IC operates from an input supply between 6V and 36V and provides an externally adjustable output current of up to 1.2Amp.

The PT6910 includes the internal switch and a high-side output current sensing circuit, which uses an external resister to set the average output current. Also the output current can be adjusted below the set value by using the external ADJ pin.

The ADJ pin will accept either a DC voltage or a PWM waveform. Depending upon the control PWM frequency, the IC will provide either a continuous or a gated output current with the internal PWM filter circuit.

The PT6910 provides a soft-start feature. And the soft-start time can be increased by using an external capacitor from the ADJ pin to ground if you need a longer soft-start time. Anyway if you apply a voltage of 0.2V or lower the output switch will be off and the IC go into a low current standby state.

FEATURES
• High Efficiency (up to 95%)
• Soft-Start (Adjustable)
• Maximum 1.2A Output Current
• Low/High Frequency PWM Dimming with Internal PWM Filter
• Wide Input Voltage: 6V ~ 36V
• Internal Open-Circuit LED Protection
• Typical 5% Output Current Accuracy
• SOT-89-5L